Notice the updated QPF map on the right which is valid through Friday morning. As was the case yesterday, it is showing OK in a precipitation bulls eye with the potential for several inches of rain during that period. The most likely time for the rain to fall will be during the Wed-Thu time frame although there will be a slight chance of showers and storms later Monday and during the day Tuesday.
This is all due to a pattern change in the upper level wind flow. A strong storm system aloft will push a trailing surface cool front into the state late Monday and Monday night. Most of the energy with that system aloft will be well north of us, so the cool front will stall out in a general E-W manner across the state for Tuesday into Wednesday. With a stationary frontal boundary draped across the state and some energy aloft moving over the boundary, that sets the stage for periods of showers and storms, some of which may be severe. Damaging winds and hail would be the primary threats.
As the flow aloft amplifies later in the week, the developing NW flow will finally push the front on out of the state for Thursday into Friday. That should set the stage for some pleasant, relatively mild weather going into the coming weekend with only some lingering showers into Friday and little or no mention of rain for the weekend.
For today and tomorrow though, we still have the hot, humid weather to contend with. Gusty southerly winds of 15-25 or more and lots of sunshine today will push daytime highs back to near the 90 degree mark. There is a threat of severe storms for far NW OK and into W KS this evening and as that activity works its way eastward, there could be a few dying showers along the OK/KS state line for the Monday morning time frame. Other than that, Memorial Day itself should be dry until that evening or more likely overnight when the front arrives.
As the front approaches Monday, the pressure gradient should begin to relax resulting in southerly winds of 10-20 and not quite as gusty as during the day today. Partly cloudy to mostly cloudy skies are also expected for Monday, with temperatures to start the day near 70 and daytime highs around 90 again. The front will eventually stall out in the vicinity of I-40 or perhaps highway 412 with a more E/NE wind behind the boundary and SE winds ahead of the boundary for Tuesday. Partly cloudy to mostly cloudy skies, the shifting winds, and scattered showers/storms Tuesday should result in daytime highs in the upper 80s.
After that, the more widespread showers/storms expected for Wed/Thu should continue to knock temperatures back to below normal for a change. As mentioned above, that is also our best chance for some good, soaking rainfall. I just hope we do not try to catch up on our rainfall deficit all at once and go from drought to flood.
So, stay tuned and check back for updates.